| dita | DITA Document |
| ditamap | DITA Topic Map |
| ditaval | DITA Conditions Data |
| dix | Stonevoice Translator Custom Dictionary |
| dix | Apertium Monodix Dictionary Data |
| diy | My Drivers Backup Setup |
| dja | DunDjinni Data |
| djd | Digital Juice Juicer Data |
| djf | NTI Backup Now Drive Backup |
| djm | Dynojet Map Data |
| djp | DJPrint Data |
| djswipes | Digital Juice Juicer Swipes Data |
| dkd | JBK Karaoke Data |
| dkf | DriveCrypt Key File |
| dkl | DupKiller File List |
| dklang | DKLang Translation Editor Translation Data |
| dkn | ONETEP Density Kernel |
| dkr | Cisco MDS 9000 DKR Data |
| dkt | d-lusion Drumstation Saved Drum Kit |
| dl | FLEXnet Manager Debug Log |
| dl4 | Lindab DIMsilencer Data |
| dla | Defense Department DLA Procurement Data |
| dlc | JDownloader Download Link Container |
| dlf | EES Dynamically Linked Function |
| dlis | Digital Log Interchange Standard File |
| dlog | EasySYNC EasyLogger Data Log |
| dlog | Avid Pro Tools Log |
| dlpext | DESlock+ Data |
| dlpf | DinkeyLook Diagnostic Information Data |
| dlt | DELTA Binary Dataset File |
| dltemp | UC Browser Incomplete Download |
| dlv | Catia V4 Export Data |
| dlv3 | Catia V3 Export Data |
| dlv4 | Catia V4 Export Data |
| dlx | DIALux Project |